(TAG hat on.)

Having fast access to be able to get say, features out of a model trained against faces is a reasonably scary vector in the aspect of privacy.

Cosine similarity between two facial features (e.g. ripped out from the last FC layer, for a pretty blunt approach) effectively enables a cross origin individual tracking tool, given that you can get the user to opt-in to getUserMedia. Probably something that will have to be considered later on.